In evaluating a patient for chronic kidney disease, which lab finding is significant?

High blood urea nitrogen (BUN) is significant in evaluating a patient for chronic kidney disease. In cases of chronic kidney disease, the kidneys lose their ability to filter waste products effectively from the blood. As kidney function declines, the ability to excrete urea decreases, leading to an accumulation of urea in the bloodstream, which results in elevated BUN levels. This lab finding serves as an important indicator of renal function and is commonly used to assess the severity of kidney impairment.

While factors such as serum creatinine levels and eGFR are also valuable in diagnosing and assessing kidney function, an elevated BUN specifically points to the accumulation of nitrogenous waste in the context of reduced kidney efficiency. Additionally, having normal serum electrolytes does not provide sufficient information about kidney function and could be misleading in the context of kidney disease evaluation. Overall, an elevated BUN is a key marker that supports the diagnosis of chronic kidney disease and aids in determining the extent of renal impairment.